Device for smoothing the surface of concrete pavements



May 25 1926. 1,536,325

(3. OLDER 'DEVICE FOR SMOOTHING THE SURFACE OF CONCRETE PAVEMENTS Filed Nov. 28, 1925 2 Sheets-sheet l f I A I 17 14 May 2.5 1926.

C. OLDER DEVICE FOR SMOOTHING THE SURFACE OF QONCRETE PAVEMENTS Filed Nov. 1923 2 Shee s-Sheet 2 it? zzyjzm Older Infe wzww

prnggq Patented May 25, 1926.

CLIFFORD onions, on SPRINGFIELD, ILLINOIS.

DEVICE FOR SMOOTHING THE suaEAc or concEE'rE :eAvEMEN'rs.

Application filed November 28, 1923. Serial No. 677,542.

This invention relates to a device for smoothing the surface of concrete pavements, and has for itsobject the provision of means to enable road builders to secure a smoother surface on concrete. roads and pzwements than has been obtained heretofore. H

lVith the in constructing concrete roads, it is exceedingly difficult to finish the surface of the road so-that'it will be free from numerous waves or, irregularities which often occur short distances apart. The use of the present invention will eliminate most of such waves and the waves which do occur will be on much more widely separated centers.

Before entering into a discussion of the specific function and operation of the present invention the structure of the device will be described in detail.

Referring now to the drawings,

Fig. 1 is a plan view of the float or apron forming a salient part of the present invention, showing it in position overthe I concrete roadway;

Fig. 2 is a view on the line 22 of Fig. 1.; Fig. 3 is a view on the line 3 -3 of Fig. 1; Fig. 1 is a side view of a motor driven carriage or support by means of which the float shown in Figs. 1, 2 and 3 may be moved about, and

Fig. 5 is a section substantially on the line 5 5 of Fig. 4.

In the drawings, indicates the earth sub-grade, 11 freshly placed concrete, and 12 the side forms between which the concrete is placed. It is to be understood, that Figs. 1 to 3 of the drawings are intended to show an ordinary concrete road in proccss of construction. The apron platform or.

float which forms the gist of the present invention consists of a plurality of longitudinally extending strips 13 which are secured together by flexible transverse strips 14'; The bottom of ythe structure thus formed is covered by means of a'flexible sheet or apron 15. A

satisfactory structure has been provided by using for the strips 13 ordinary 2- X 4".

wood strips placed 4". to apart, and for the transverse strips 14: ordinary'boards.

The flexible sheet 15 may be of very heavy canvas or of sheet metal, the surface ofwhich has been roughened as byfslight cor rugations. It has been found that a smooth a r asa he-traumas bi reli hes asaapparatus at present employed means of the somewhat or smooth boards does not operate satisfactorily as it tends to cause the float to slide over some of the wave crests instead of smoothing them down. The float used is of large area, preferably of such width as to extendfrom edge to edge of the road,

and may be 6. or 8 long, or, under certain circumstances, a length of 15 or even 18 may be found desirable.

Briefly stated, the device is employed by dragging ita-long on the surface of the con crete' while it is in a soft condition, and operates to rub off the crests of the waves 1 inthe concrete and force the material forming the crests lnto the troughs of the waves,

thus producing a practically smooth surface.

In Figs. land 5 a motor driven carriage is shown which may be used to operate the float. This carriage comprises the wheels 16 joined by the mile 17 and the like pair of wheels 18 which are joined by an axle simi lar to 17. Supported above the axles are the pair of cross members 19 and 20 which carry the longitudinally extending side members 21 and 22. Carried by each of the side members 21 and 22 are thetruss frames 23 and 21 joined by the transversely extending members 25. Rotata-bly mounted on the truss frames 23 and 24 are a pair of transversely extending shafts 26, each of which is provided with a ratchet wheel 2'? adapted to be engaged by a ratchet 28 to prevent reverse rotation thereof. Each of. the shafts is also provided with a crank 29 by means of which the shaft may be rotated.

\ A plurality of flexible devices 30, as ropes I or, chains, join each of the shafts 26 to a transverse member 14 of the float. The transverse member let at the left in Fig. 4:

at the forward end of the float is also joined to theforward endof the carriage by means ofthe chain or rope 31. The wheels 16- and 18 are preferably arranged to travel on' the upperedges of the side forms 12.

1" hen the device is in operatiointhe ropes 30 will be slaclr, permitting,thefloat to rest squarely on the upper surface of the cement the float being drawn along at this time by means of the chain 31. Any desired means may be providedfor moving the carriage along, but it will preferably be provided with a small horsepower motor 32 which will be joined to the shaft 17 by any suitable reducing. gearing. IA direction-reversmg area-ear a s.- .11 ii f rab y cr ded in the transmission 'so that the carriage may be run backward as well as forward. As this'mechanism is exceedingly old and well known it is neither shown nor described in the present disclosure. In some cases it will be found desirable to so'proportion the gearing that the carriage may be caused to travel along the road at approximately the average rate of construction, thus making unnecessary tt'requent' stopping and starting of the carriage motor.

The shafts 26 are employed to raise the float'only when it is desired to move the devicefrom place to place, or'when it is desired to more the device backward so as again to pass the float over a surface of the road which was not properly finished by the preceding operation.

In order that thepresent invention'may be better understood, certain typical proc esses such ashereto'fore employed willbe described briefly.

In the operation of the present device and other surfacing devices, theconcreteis first dumped. between the side forms and then is-roughly' leveledby means of hand,

operated shovels. The surface of the road is then further smoothed by means of a heavy template orstrikeboard, the lower edge of. which is of acontour corresponding to-the desired surface contour of the. road, and-is dragged over the surface of the con crete by workmen, one positioned at each side of the roadway. This strikeboard has its ends preferably rested on and guided by the ecges of the side forms. After the strilz'choard' has been passed over the surface ofthe concrete, if depressions or hol lows still occur in the surface, they are tilled by hand shovelers', and the strikeboard is again moved overthe surface. This procis repeated until the road has been given a fairly even surface. However, as the ends of'the strikeboard are guided by the edges of the side forms, the surface will be no smoother than the. edges of the side forms are straight, and as the edges of the side forms rapidly become worn and uneven and.

are sometimes oi'fset'where the ends join, it results in an uneven'surface of the road. l urthermore, in the operation of the strike.- board, there is a constant't-endency for the board to beelevated slightly off from the edges ofrthe' side forms when the crest. of a large wave is reachechor where the concrete is unu'sualy thick, so that the road surface is actually less even than are the edges of the sideforms.

It also has beencustomary heretofore to uses leveling machine, which consists of a motor driven carriage which may be roughly similar to thatshown in Figs. at and 5, having a rollermounted adjacent to one end. The carriage isfirst propel-led over the roadreverse direction in order to force the tops of the crests of the wavesinto the depressions. After a fairly smooth surface has been obtained, the carriage is moved over the roadway with the roller rotating in the other direction, thatis, rolling along the surface of the roadway, in order to compress the materialandfurther smooth the surface. However, with this sort of apparatus, as ith the hand operated strikeboard, the device is guid'edby the edges of the side form and the road surface can be no morelevel than are the edges of'the side forms.

Either of the old processes just described may be used in preparing a road surface for the use of the present smoothing arrangement, as the invention is not intended to supersede presentanethods of'striking off and consolidating concrete but is to be used only after the road surface has been made fairly level in order to secure a smoother surface than heretofore.

In previous processes, after the above levcling operation has been carried out, the surface of the road' is further finishedby means-of a belt 8 or perhaps 10 Wide, which is laid transverselyacross. the road anddraggedforward by workmen, one on each side, with a back andforthlengthwisemotion. The belt, however, does not act appreciably to smooth'outthe waves in the surface of the roadway, but merely acts to give the surfacea finer texture. In'using the presentdevice, after the concrete has been leveled roughlyby anyone of the previously employedunethods, such as the strikeboard or the motor driven carriage having'the roller, the float herein described will be employed merely to further smooth the road surface and obviate the various transverse waves which often occur close together in roadways and cause a great deal ofvib'ration to rapidly moving vehicles.

Applicants float may be drawnv over the roadway by attaching it behind the. carriage of a finishing machine, such as the one above mentioned employing the roller, when it passes over the road the last time, or it may be provided with a'special carriage, suclras the one shown in Figs. 4 and 5. At any ratepthis device, due to the factthat it is of large surface and extended lengtlnwill operate to smoothtofi' the crests ofthe short center waves provided by thestrikeboard or other device guided by the edges of-jthe side formal-and push the crestsinto the hollows, forminga more nearly smooth surface. As the float herein disclosed is'not guided by the edges of the form at any particular point, when it is used the. small unevennesses in the side forms will not operate to'cause irregularitiesin the road surface. Furthermore, due: to the extended length of the float, ifanyawaves-or irregularities 'do'occur, they "must 'oc'ci'ir on centels'wll'ich" cannot-"be gether, and

less than the length of the float, and, therefore, will be so far apart as to have little, if any effect on vehicles which are traveling at ordinary speeds.

In place of the 2 x & strips 13, such as herein shown, angle or channel iron strips may be employed, and likewise slightly flexi ble metal strips may be used in place of the boards 14. In certain cases, ing the transverse strips 14: somewhat flexible in order that'the float may accommodate itself to the transverse crowned contour of the roadway, it may be desirable to give the float a definite transverse contour to correspond to the arched surface desired in the finished road, in which case the transverse members will be rigid instead of flexible, as herein disclosed.

A float having the same function and operation as the one herein described may be formed in many ways, the main requirement being that it shall be of extended area so as to obviate the short center waves which are so prevalent in the surfacesof most concrete roads at present constructed.

Having thus described my invention, what I claim as new and desire to secure by Let-v ters Patent of the United States is:

1. A float for smoothing the surfaces of concrete roads under construction comprising a plurality of substantially parallel rigid strips arranged in slightly spaced relation, transverse members securing said strips toan apron of sheet material underlying said strips and extending from side to side of said float.

2. A float for smoothing the surfaces of concrete roads under construction comprising a plurality of narrow substantially parallel rigid strips arranged in slightly spaced relation, transverse members securing said strips together, and an apron of sheet material ha'ving a slightly rough lower surface underlying said strips and extending across the spaces therebetween.

instead of male gether and permitting relative vertical movement between said strips, and an apron 0t flexible material underlying said strips.

l. In combination, a vehicle having wheels for rolling on the sides of a'concrete road, a

float slung substantially under the vehicle, said float con'iprising a frame relatively rigid in a direction lengthwise of the road and slightly flexible transversely of the road, I

an apron of sheet material facing the under side of said frame and extending continuously from side to side thereof, draft means connecting said vehicle to one end of said float, said draft means permitting free rise and fall of said float, and means on said vehicle for raising and lowering said float, said latter means in its normal condition removing all pressure from said float whereby the smoothing surface of said float is caused to float on the concrete surface merely under the weight of said float and without the application of external pressure.

In combination, a vehicle, wheels on said vehicle adapted to have traction along the sides of a concrete road, power means on said vehicle for driving the same, a float slung under said vehicle, said float being relatively long to distribute any irregularities in the concrete surface over widely spaced centers, flexible draft means between said vehicle and one end of said float, and flexible means on said vehicle for raising and lowering said float, said flexible means being operable to take all pressure off of said float in normal operation whereby said float is supported directly on the road surface merely under its own weight.

In witness whereof, I hereunto subscribe ,my name this22nd day of November, 1923.

CLIFFORD owns. 

